Geometric instrument for azimuth sightings

ABSTRACT

An instrument particularly adapted for use in fire watch towers, artillery observation and the like for taking an azimuth reading on a remote smoke, target, etc., including a portable instrument readily mounted on support tracks and reciprocable in two directions at right angles to each other, including an element journaled for rocking adjustment about horizontal axes and having supported thereon a platform upon which a telescope is adjustably supported, and in which a fine adjustment for rotating the telescope about a vertical axis includes a quick-release coupling.

Davis [54] GEOMETRIC INSTRUMENT FOR AZIMUTH SIGHTINGS Feb. 15, 1972 FOREIGN PATENTS OR APPLICATIONS 299,618 10/1919 Germany ..33/67 [72] Inventor: Gerome Davis, General Delivery,

Florence, Oreg. 97427 Primary Examiner-Robert B. Hull Filed: Nov- 17, 1969 Attorney-Alexander B. Blair [21] Appl. No.: 877,148 [57] ABSTRACT An instrument particularly adapted for use in fire watch [52] US. CI ..33/67, 33/69 towers, artillery observation and the like for taking an azimuth It. 2 reading on a remote smoke target etc ingluding a portable [58] Fleld of Search ..33/67 instrument dil t d n u port tracks and reciprocable in two directions at right angles to each other, including an [56] References cued element journaled for rocking adjustment about horizontal UNITED STATES PATENTS axes and having supported thereon a platform upon which a telescope IS ad ustably supported, and in which a fine ad ust- I,027,855 5/1912 Knapp ..33/67 ment for rotating the telescope about a vertical axis includes a 1,6 I Fisher. quick-re]e3se coupling 1,978,476 /1934 Reineke. ..33/67 3,302,293 2/1967 French ..33/67 8 Claims, 7 Drawing Figures 54 65 4 m ei 46 7a, 9 69 8- y i r I 44 '3Z" 5: *1 4;

, 00 W O 0 3 W n 4 SHEET 1 OF 2 L TOR. 6590445 Mm ME.

PATENTEDFEB I 5 I972 SHEET 2 OF 2 INVL'N TOR.

BY 65mm M ws Arm/m5).

1 GEOMETRIC INSTRUMENT FOR AZIMUTH SIGHTINGS This invention is directed to an improved geometrical instrument for taking azimuth readings.

PRIOR ART Instruments used for fire watching, etc., in the past have generally been cumbersome, heavy, awkward and not readily manipulated, and merely rough approximating devices.

OBJECTS OF THE INVENTION Primary objects of the invention are to provide an improved instrument which includes a unique support carriage facilitating manipulation and adjustment of a telescope; to provide a novel portable azimuth instrument particularly adapted for use in fire watch towers, etc.

These together with other and more specific objects and advantages will become apparent from a consideration of the following description when taken with the drawing, by way of example, and in which:

In the drawing:

FIG. I is a top plan view of the instrument incorporating the invention;

FIG. 2 is an elevational view looking into the lower edge of FIG. 1;

FIG. 3 is an enlarged, fragmentary vertical elevation taken substantially on the plane ofline 3-3 of FIG. 2;

FIG. 4 is a vertical section taken substantially on the plane ofline 4-4 ofFlG. 2;

FIG. 5 is an enlarged, fragmentary section taken on the plane ofline 55 of FIG. 1;

FIG. 6 is an enlarged, fragmentary vertical section taken on the plane ofline 66 of FIG. 2; and

FIG. 7 is an embodiment of the gear arrangement of FIG. 3 supplemented with a vernier dial.

DESCRIPTION OF THE PREFERRED EMBODIMENT Fire lookout towers can be up to several hundred feet high and include windows opening toward all compass directions. A map of the area will be oriented and will be of a convenient scale enabling the watcher to readily orient the map with respect to known compass directions. During the periods when a fire watch is maintained, a geometrical instrument is generally provided, and is conveniently described as an azimuth reader." The watcher on duty must often carry the instrument aloft and this can prove to be a considerable task if the instrument is heavy.

Referring to FIGS. 1 and 2, an improved instrument to be used with a local map is indicated generally at 10. A support panel 12 has opposed, parallel track members 14. The tracks 16, fixed to base 120, include dovetail openings 18 for accommodating track members 14. A block 122 is secured to the bottom of support 12 and overlaps with a block 124 secured to the top of base 120 so that the blocks will meet and prevent further movement along tracks 16 just prior to reaching the center of gravity of support 12 and the instrument supported thereby in order to prevent sliding and tipping from surface 120.

Reciprocably supported on the tracks 20 is a rectangular support platform 22 which includes at its corners dependent wheel assemblies 24 including plastic rollers 26 produced from Nylon" or the like. The rollers 26 facilitate movement of the platform 22 along the tracks 20.

The platform includes a central, vertical bolt 28 to which is fixedly threadedly connected a substantially spherical support ball 30; the ball having a lower flat side 32 which is thus clamped to the platform 22. Overlying the ball 30 is a spherical shell 34 having a split portion 35 and arcuate slots 36 through which stop-screws 38, secured in ball 30, extend. The stop-screws will permit oscillation of the shell 34 relative to the ball 30 about horizontal axes only; see FIG. 2. The shell can be clamped at a selected tilt relative to the ball and platform by means ofa fastener 39 extending through split portion 35.

Secured to the lower edge of shell 34, and spaced circumferentially at 45 intervals are supports 40, the outer ends thereof being secured at the outer edge of a circular plate 42 which includes a chamfered upper edge 44 divided into degrees ofa circle.

A circular disc 46 is fixed on plate 42 and an annular ring 47 includes ball elements 48 received in an annular groove 49 in the upper surface of plate 42. A circular map M of the area being watched" will rest on the upper surface of plate 46, and will be fixed" and attached by snaps (not shown) which fit into an annular groove 132 of plate 46, and the ring 47 will rotate about the map M. Secured to ring 47 are telescope support rods 50 and 52 which are at right angles to each other. The rod 50 is also a mileage measuring scale divided into inches and reciprocably supports a pointer element 54 which can be readily moved relative to the map M to approximate distances relative to familiar landmarks. Element 50 measures outward from the center of map M where a center pin 100 is attached to plate 46. The support 52 pivotally mounts a telescope assembly 56 which is focused in the conventional manner. The telescope assembly includes forward and rear gun sights" 58 and 60.

As best seen in FIG. 2, secured below telescope assembly 56 is a bubble level inclinometer 56a. Level 56a is marked with conventional degrees and is basically used for night sightings when it is extremely difficult to determine distance from the lookout tower. The bubble moves within level 56a to the particular degree mark as the telescope is tilted a certain amount. Level 56a also includes an additional bottom scale which allows compensation of the reading for difference in tower heights or terrain.

As seen in FIG. 3, the telescope assembly includes a depending gear rack 62 meshed with a pinion gear 64 keyed to a transverse shaft 66 journaled in vertical uprights 68. The uprights 68 are suitably secured to ring 47. Secured to the shaft 66 is a knurled handle or knob 69 and the telescope assembly 56 can be adjusted about the support 52. A fine adjustment is provided to rotate the telescope assembly 56, i.e., annular support ring 47, 360 relative to the map M and scale 42. The plate 46 includes a circumferential, upwardly disposed annular gear rack 70 and a pinion gear 72 is meshed therewith. The gear 72 is journaled on a spring-urged frame 74 reciprocably supported on one upright 68. The frame 74 pivotally supports a lever which will engage an abutment 82 and the pinion gear 72 can be laterally displaced with respect to a vertical worm gear 84. The gear 84 is journaled on a suitable support element 86, and includes an upper bevel gear 88 meshed with a driving, bevel gear 90 keyed on shaft 92 journaled on the supports 68 below shaft 66. The shaft 92 includes a knurled knob 94 at one end, and rotation of the knob 94 causes the telescope assembly 56 to move on ring 47 about the circular map M on plate 46. Rotation of knob 69 orients the telescope 56 vertically by raising or lowering gear rack 62 which is connected to telescope 56 by means of hinge I30. Additionally, in emergencies, the lever 80 can be pivoted outwardly, disengaging gear 72 from worm gear 84 and the telescope can be manually rotated directly.

FIG. 7 illustrates an embodiment of the gear arrangement wherein a second gear 102 is axially connected to gear 72. The pointer 106 of a dial 108 is connected to a small gear 110 which is engaged with teeth 112 of a gear 114 that meshes with gear 102. When gear 72 turns, the revolving pointer 106 will shown the minutes of the degree indicated directly below on upper edge 44.

OPERATION Briefly, tracks 16 and 20 permit translative adjustments to a convenient viewing position; the wheel assemblies 26 facilitating movement; The ball 30 also permits limited universal rocking movement of the plate 42, etc. The telescope can be readily sighted in on suspected smoke by means of adjusting knobs 69 and 94; and the rod 50, alignable with scale 44, will assist the watcher" to determine the compass direction with respect to the map M, and with pointer 54 the approximate distance of the smoke can be ascertained on scale 50. The dispatcher offirefighters" can call in the compass direction and approximate location of the smoke to an adjacent watch station and when receiving a new compass direction, by intersecting the two compass directions. can locate the exact vicinity as to the township, range, and section of a suspected fire; this facilitating firefighter by plane, truck, etc.

I claim: 1. A geometrical instrument for taking azimuth sightings and approximating distances of said sightings comprising a base, a support member, interengaging horizontal track means connecting said base and said member for linear horizontal adjustment of said member on said base, platform means spacedly mounted above said support member for movement to any location in a horizontal plane area above said support member, track means mounted on and extending adjacent said support member and said platform means and including a above said circular map support and rotatable azimuthally relative thereto 360 about the center of the map support, and

means including a distance scale supported diametrically relative to said map and rotatable with said telescope assembly and a pointer having radial movement therealong relative to the center of the circular map support for indicating with said pointer and distance scale the approximation of the distance to a point being sighted upon.

2. The structure as claimed in claim 1 in which said circular map support includes a central circular area for removably supporting a map of an area being observed, and further comprising an annular ring journaled for rotation about said central circular area and supporting said telescope assembly and said indicating.

in which said map support includes a circular scale surrounding said annular ring and including indicia thereon dividing said scale into 360.

4. The structure as claimed in claim 2 including means supporting said telescope assembly for horizontal axis pivotal movement about a transverse support axis, and means for manually and incrementally pivoting said telescope assembly about said transverse support axis.

5. The structure as claimed in claim 4 in which said circular map support includes an annular gear rack extending 360 thereabout, and further comprising a gear drive meshed with said gear rack and connected to said telescope assembly, and a manually operable operator connected to said gear drive for incrementally rotating said telescope assembly about the center of said circular map support.

6. The structure as claimed in claim 5 including quicktive movement therebetween.

8. The structure of claim 7, wherein said shell has arcuate slots and wherein said limiting means includes projections from said spherical element slidably mating with said Slots. 

1. A geometrical instrument for taking azimuth sightings and approximating distances of said sightings comprising a base, a support member, interengaging horizontal track means connecting said base and said member for linear horizontal adjustment of said member on said base, platform means spacedly mounted above said support member for movement to any location in a horizontal plane area above said support member, track means mounted on and extending adjacent said support member and said platform means and including a plurality of transverse tracks slidably holding said platform means above said support member for relative linear horizontal movement thereabove, perpendicular to the movement of said support member on said base with the physical orientation of said platform means being fixed relative to said support member, a circular map support overlying said platform means, means providing for universal tilting movement between and connecting said map support to said platform means, a telescope assembly, means supporting said telescope assembly diametrically above said circular map support and rotatable azimuthally relative thereto 360* about the center of the map support, and means including a distance scale supported diametrically relative to said map and rotatable with said telescope assembly and a pointer having radial movement therealong relative to the center of the circular map support for indicating with said pointer and distance scale the approximation of the distance to a point being sighted upon.
 2. The structure as claimed in claim 1 in which said circular map support includes a central circular area for removably supporting a map of an area being observed, and further comprising an annular ring journaled for rotation about said central circular area and supporting said telescope assembly and said indicating.
 3. The structure as claimed in claim 2 in which said map support includes a circular scale surrounding said annular ring and including indicia thereon dividing said scale into 360*.
 4. The structure as claimed in claim 2 including means supporting said telescope assembly for horizontal axis pivotal movement about a transverse support axis, and means for manually and incrementally pivoting said telescope assembly about said transverse support axis.
 5. The structure as claimed in claim 4 in which said circular map support includes an annular gear rack extending 360* thereabout, and further comprising a gear drive meshed with said gear rack and connected to said telescope assembly, and a manually operable operator connected to said gear drive for incrementally rotating said telescope assembly about the center of said circular map support.
 6. The structure as claimed in claim 5 including quick-release coupling means interposed between said gear drive and said manually operated whereby the telescope assembly can be rapidly swung independently of said gear drive.
 7. The structure as claimed in claim 1 in which said means connecting said map support to said platform means comprises a generally spherical element projecting from said platform means, and a generally spherical shell rockably mounted on said spherical element and including means limiting relative movement therebetween.
 8. The structure of claim 7, wherein said shell has arcuate slots and wherein said limiting means includes projections from said spherical element slidably mating with said slots. 